Catch thread loom attachment



March 14, 1967 A. L. POWER ETAL 3,308,855

CATCH THREAD LOOM ATTACHMENT Filed Aug. 26, 1965 4 Sheets-Sheet 1 INVENTORS ANGUS L.POWEF FFD9 LVEVDffidAiS ATTORNEY March 14, 1967 A. L.. POWER ETAL 3,308,855

CATCH THREAD LOOM ATTACHMENT Filed Aug. 26, 1965 4 Sheets-Sheet 2 RA GK CLUTCH COLLAR .SPUR GEAR '22 SUPPORT INVENTORSQ ANGUS L. POWER FRED WE/DHAAS ATTORNEY March 14, 1967 A. L. POWER ETAL 3,308,855

CATCH THREAD LOOM ATTACHMENT Filed Aug. 26, 1965 4 Sheets-Sheet 3 INVENTORS. A/VGUS L. POWER FRED WE/DHAAS March 14, 1967 A. POWER ETAL CATCH THREAD LOOM ATTACHMENT 4 Sheets-Sheet 4 Filed Aug. 26, 1965 INVENTORS mvaus L. POWER' FRED WE/DHAAS BY @MMMM 1 ATTORNEY United States Patent Ofifice CATCH THREAD LOGM ATTACHMENT Angls L. Power, Medfield, and Fred Weidhaas, Eastham'pton, Mass., assignors to United Elastic Corporation, Easthamptou, Mass, a corporation of Massachusetts Filed Aug. 26, 1965, Ser. No. 482,749 5 Claims. (Cl. 139-416) This invention relates to an improved catch thread loom.

In ordinary shuttle looms the weft thread, or weft threads in the case of multiple weft weaves, are passed through the shed formed by the warp threads suitably separated by heddles in accordance with the weave pattern desired. After each pick the weft beaten in by conventional reeds which move down the warp threads. This ordinary weaving, which has been used for centuries, depends on the weft thread being carried through the shed by the shuttle, which is often a circular shuttle, particularly on gang looms weaving multiple webs. The weft thread is carried on a quill in the shuttle, and because of the circular shuttle size and shape there is a very definite limit on the amount of thread or yarn carried by the quill. When the quill is empty, of course weaving has to stop and a new quill or bobbin inserted in the shuttle and the new thread tied to the old with a traditional weavers knot. Each time a quill or bobbin has to be replaced, this is done by hand and increases the labor cost substantially and at the same time reduces the output from a given loom because, of course, weaving is stopped while replacing a bobbin or quill in the shuttle.

Another, though not quite so serious, drawback occurs in the case of multiple weft looms. Here the bobbins for the shuttles weaving the different weft threads may not run out at the same time because in certain weaves the amount of one kind of weft thread may be greater than another. Even when the weft threads are the same in length in the final weave, the quills or bobbins may not have exactly the same length of thread on them, and so, in such a case, if one bobbin or quill runs out of thread it may be considered more economical to replace the bobbin or quill of the other shuttle at the same time even though it still may have some thread on it. A certain amount of waste thus results.

In 1901 a new type of loom was proposed by Fischer and is described in US. Patent No. 671,820. In this type of loom the actual weft thread is not in the shuttle at all but carried on a large cone, which may have many miles of thread and so last for many hours, much longer than is possible with the amount of thread on a bobbin or quill in any practical size circular shuttle. The shuttle, as it moves backward and forward through the shed, catches the weft thread, pulls it across through the shed in the form of a loop and on its return binds the Weft thread to one of the sides of the fabric woven. Since the length of this catch thread is very short compared to the length of the weft thread pulled across the shed by it and bound, an ordinary bobbin or quill in a shuttle will last for many more hours than in ordinary weaving. As a result, weaving can continue for long periods of time, increasing the output of a loom, and the labor of changing bobbins or quills which have run out of thread is decreased, often considerably more than an order of magnitude, depending of course on the width of the fabric woven, for the small length of the catch thread which binds the actual weft thread at each double pick is substantially the same for wide fabric as narrow.

Despite the great theoretical advantages of the Fischer loorn, which today is normally referred to as a catch thread loom, a nomenclature which will be used through- 3,308,855 Patented Mar. 14, 1367 out the remainder of this specification, it did not imme diately go into any practical use. For this there may have been two reasons, one of which is certain. In 1901 wages were very low and so the additional time required for ordinary weaving did not represent as serious a cost factor as it does today with the enormously increased labor costs. Another, and very serious factor, which still holds true today, is that as the catch thread from the shuttle pulls the weft thread through the shed, the length of the loop of catch thread at the end of the shuttles travel will vary depending on the friction that occurs as the weft thread is unwound and is pulled through its customary tensioning means. As a result, it proved to be practically impossible to maintain the loops of the catch thread exactly uniform. This resulted in a somewhat imperfect appearance of the edge of the fabric where the weft thread is caught and bound by the catch thread. This drawback in uniformity of quality is very much greater with wide fabric than with narrow fabric because the friction of carrying the weft thread through the shed of a wide fabric is harder to maintain constant than with a narrow fabric. This reason probably was the most important factor in the failure of the Fischer loom to achieve practical success.

Some sixty years later, the catch thread principle was once again investigated, and it was found that with nar row webbing the appearance resulting from the nonuniformity of the binding loops of the catch thread could be tolerated in certain fabrics where appearance is not so serious a factor, for example elastic webbing inserts in shorts, pajama trousers, and other garments where the non-uniform edge is not too serious a drawback. However, even with narrow webbing the non-uniformity of the resulting product seriously adversely affected sales. While a certain amount of narrow fabric or webbing was woven in the early sixties by the catch thread method,

the field of usefulness was rather seriously adversely affected. It is with an enormous reduction and in most cases practically complete elimintaion of this drawback that the present invention deals.

According to the present invention, a precisely and exactly predetermined length of weft thread is fed to the loom at each double pick. There is, therefore, no tension on the weft thread other than the very small amount of friction as it is drawn through the shed, and so the catch thread always pulls the weft completely across and forms small, uniform, and neat binding loops. It is an advantage of the present invention that it can be used with single weft fabrics or multiple weft fabrics and that all of the advantages of the catch thread loom principle are retained while producing uniform, perfect fabrics.

The invention will become more clear in connection with the drawings, in which:

FIG. 1 is a side elevation of a catch thread loom;

FIG. 2 is a detailed view on an enlarged scale of one desirable method of weft thread feeding;

FIG. 3 is a semi-diagrammatic illustration of the catch thread weaving; and

FIG. 4 is a side elevation of a modified form of weft thread feeding mechanism.

Turning to FIG. 3, a webbing is shown with warp threads 1, for example covered elastic threads. As the customary mechanisms for forming the shed, namely heddles, and for beating in the weft are not changed in the slightest by the present invention, these elements have been omitted to show the weave more clearly. Also, the illustration is of a circular shuttle, which is common in looms for weaving multiple webbing.

The weft thread 2 is unwound from a very large cone 12 (FIG. 1), which can accommodate many miles of weft thread. The weft thread is unwound through a customary tension means comprising plates 28 and a spring 30. As the tensioning means is conventional and its exact construction forms no part of the present invention, it is illustrated purely diagrammatically in FIG. 1. The weft thread passes under a guide bar 3 and is caught by thread 6 from a shuttle 5, the thread being unwound from the conventional bobbin or quill 4 and being provided with side springs 7. The thread emerges from the center of the circular shuttle 5 through an opening 8. In order not to confuse the drawing, the conventional arced groove tracks of a rotary shuttle are not shown as they are not changed by the present invention. In fact it is an advantage that the modifications producing the improved results of the present invention can be applied to any conyentional loom. As the shuttle 5 moves to the right, the catch thread 6 pulls the weft thread 2 across the fabric through the shed. FIG. 3 shows the shuttle at about twothirds of its travel. The drawing is intended to be a diagrammatic illustration and so a relatively coarse weave is illustrated to avoid confusion of the drawing with an excessive number of warp threads.

When the shuttle is moved all the way to the right, the weft thread is beaten up to form the double pick and the heddles move in the conventional manner so that on the return or left hand travel of the shuttle the catch thread 6 binds the weft thread at the edge of the fabric. This can be seen at the bottom of FIG. 3 where a few picks of the final webbing are illustrated. It will be seen that the loops of the catch thread 6 are absolutely uniform and are, of course, very short, so that the length of catch thread used even in the fairly narrow webbing illustrated is an order of magnitude less than the length of the weft thread. So far the description would be applicable to an ordinary catch thread loom. The new features of the present invention will, therefore, now be described.

Turning to FIG. 1, the main loom drive shaft 9 'is shown at the back of the loom with a gear 29 partly broken away to show its teeth. This gear meshes with a larger gear 10 which rotates freely on its shaft, (not shown). The gear 10 carries a framework 19 in which an eccentric pin can be moved by a fine adjusting screw 17 turned by a head 18. The particular position of the pin can then be locked by the lock nut 16. Pin 15 can move in a slot in an arm 11 which is pivoted at 13 on a bracket 37 on the 100111 framework. The other end of the arms carries a fork 14 in which a pin 31 of a shaft engages. The shaft moves through a suitable sleeve 32. The result of the rotation of the gear 10 is to move the shaft 20 up and down a predetermined distance determined by the adjustment of the screw 17. This movement of the arm 11' and fork 14 is shown diagrammatically in dashed lines in a second position in which the pin and the shaft 20 has been moved up to its uppermost position.

A preferred form of weft feed is illustrated in FIGS. 1 and 2. This feed is driven by a rack 21 on the rod 29 and a pinion 22 on a shaft 25, best seen in FIG. 2. The shaft drives through an overrunning or one-way clutch 24 a feed wheel 23 around which a turn or two of the weft thread 2 is wound. The shaft 25 is held in a journal 26 which is bolted to the loom frame by bolts 27. When the rod 20 is in its lowest position, which is shown in the solid lines in FIG. 1, this corresponds to the extreme left hand travel of the shuttle 5. The heddles change the shed and the shuttle starts on its return travel to the right, having caught the weft thread 2. Now, as the shuttle moves the arm 11 moves the rod up. This causes the feed wheel 23 to turn, because the over-running clutch locks so that the wheel is driven as shown by the curved arrow in FIG. 1. It pulls out through the pressure plates 28 and spring 30 a predetermined length of weft thread 2 from the cone 12. It should be noted that this is a positive drive and the predetermined length which is set by the adjusting screw 17 will be drawn out regardless of variathe thread from the cone 12. The adjustment is made so that the length of weft thread drawn by the wheel 23 is almost exactly equal to the length for one double pick. In other words, the thread is fed to the shed without tension and in exactly the right length so that when the shuttle has moved to its right hand position the loop of the weft thread will be drawn all the way over and a binding loop of the catch thread results which is of uniform, minimum length, as illustrated at the bottom of FIG. 3.

When the heddles now change the shed, the shuttle proceeds to the left, the rod 24} moves down, but now the feed wheel 23 is not turned because in this direction of rotation the clutch 24- simply overruns or free-wheels.

After the shuttle has reached its extreme left hand position,

the rod 26 again rises and the feed wheel 23 feeds another predetermined length of weft thread as has been described above.

Reference has been made to feeding weft thread from one or other side of the fabric. If there are two weft threads, one can be fed from one side and the other from the other. FIG. 1 illustrates the situation where the feed is from the left side of the webbing, which is also shown in FIG. 3. If it is to feed from the right hand side, then the clutch must be turned around or adjusted so that the feed wheel turns clockwise when the clutch takes hold and not counter-clockwise as illustrated in FIG. 1. If there are two weft threads, one from the right and one from the left, the catch thread will pull them across each time and, of course, the feed mechanisms will be actuated in both travels of the rod. The right hand feed with clockwise rotation of the wheel 23 which, of course, feeds the same predetermined length of weft thread because the travel of the rod 26 is the same whether it is moving up or down.

Extensive adjustments are possible with the adjusting screw 17, or if the new fabric is to be very much different in width, it is possible to effect even greater change of movement of the rack 21 by changing the sizes of the gears 29 and 10. Once set, however, for a particular fabric width, the length of weft thread fed remains absolutely V uniform.

FIGS. 1 and 2 have illustrated a preferred form of feed. However, any feed which will pull out a predetermined length of weft thread can be used. Another form is illus= t-rated in FIG. 4 which has somewhat simpler mechanism but not quite as perfect an elimination of friction. In this modification a projection 33 on the rod 20 carries a roller 34 which, on movement of the rod in one direction, pulls thread from the cone 12 and on the travel of the rod unwinds a predetermined length, whereas on the reverse movement the length pulled out is slack and feeds over the guide bar 3 is exactly the same manner as in FIGS. 1 and 2. The roller 34 cooperates with another roller 37 when the feed from the left hand side of the fabric is desired. This is shown in FIG. 4 in solid lines for the weft 2. When it is desired to feed from the opposite side, rollers 35 and 36 are needed and the travel of the thread is shown in dashed lines. Needless to say, in the case of left hand feed the thread is pulledout on the upward movement of the rod 25 and then is fed slack to the guide bar 3 as the roller 34 moves down. In the situation for right hand thread, of course the thread is pulled out when the rod moves down and is fed over the roller 36 to guide bar 3 when the rod rises.

The simple, rugged mechanical drives for the two modifications of feed illustrated have much to commend them, particularly the positive feed illustrated in FIGS. 1 and 2. However, in its broader aspectsthe present invention is not concerned with any particular means for feeding a predetermined length of weft thread to the catch thread on its travel through the shed in the direction where it pulls the weft thread. The invention, therefore, is not intended to be limted to the drives shown, which are illustrative only, although in a more restricted aspect these 5 particular designs form a more specific aspect of the invention.

We claim:

1. In a catch thread loom in which at least one weft thread from external supply sources is pulled through the shed of the warp by a catch thread carried by the loom shuttle, which catch thread also binds each weft thread on at least one edge of the fabric, the shuttle having a controlled travel without overshoot, the improvement which comprises,

(a) means driven synchronously with shuttle travel for withdrawing a precisely predtermined length of each weft thread from the external thread sources and feed the predetermined length to the catch thread without tension during the shuttle travel in which the catch thread pulls the weft through the shed, the length so withdrawn and fed being substantially equal to the length of weft thread in a double pick, whereby the loops of catch thread binding weft threads at at least one edge of the fabric are of uniform length and a fabric of uniform edge appearance is produced.

2. An improved catch thread loom according to claim 1 in which the weft thread withdrawn means comprise,

(a) a reciprocating member,

(b) means for driving said reciprocating member in synchronism with loom shuttle drive through a travel proportional to the predetermined length of Weft thread fed.

3. An improved catch thread loom according to claim 2 in which the drive means comprise,

(a) a gear driven in synchronism with loom main drive, a second gear meshing therewith,

(b) a pivoted arm and eccentric drive means associated with the second gear for oscillating said arm,

(c) means for varying the radial position of the eccentric drive and for looking it into adjusted position, and

(d) means for driving the reciprocating member from the oscillating, eccentrically driven arm.

4. An improved catch thread loom according to claim 3 in which the reciprocating member is provided with a rack driving a pinion and the latter drives through an overrunning clutch a weft thread withdrawing wheel, the drive and clutch direction being synchronized so that the weft thread is fed under no tension to the catch thread in proportion and as it is drawn through the shed by the catch thread.

5. An improved catch thread loom according to claim 3 in which the reciprocating member carries a projection around which weft thread can be passed and which in one direction of motion pulls out a predetermined length of weft thread and on the return motion feeds it slack to the catch thread as the shuttle carries the latter through the shed.

References Cited by the Examiner UNITED STATES PATENTS 671,820 4/1901 Fischer 139-117 2,165,890 7/1939 Foster 139-123 X 2,5 89,429 3/ 1952 Pfarrwaller 139-126 3,076,483 2/1963 Pfarrwaller 139-126 FOREIGN PATENTS 202,246 6/ 1956 Australia.

567,83 6 3 1945 Great Britain.

MERVIN STEIN, Primary Examiner. H. S. JAUDON, Assistant Examiner. 

1. IN A CATCH THREAD LOOM IN WHICH AT LEAST ONE WEFT THREAD FROM EXTERNAL SUPPLY SOURCES IS PULLED THROUGH THE SHED OF THE WARP BY A CATCH THREAD CARRIED BY THE LOOM SHUTTLE, WHICH CATCH THREAD ALSO BINDS EACH WEFT THREAD ON AT LEAST ONE EDGE OF THE FABRIC, THE SHUTTLE HAVING A CONTROLLED TRAVEL WITHOUT OVERSHOOT, THE IMPROVEMENT WHICH COMPRISES, (A) MEANS DRIVEN SYNCHRONOUSLY WITH SHUTTLE TRAVEL FOR WITHDRAWING A PRECISELY PREDETERMINED LENGTH OF EACH WEFT THREAD FROM THE EXTERNAL THREAD SOURCES AND 